Army investigators have concluded that traces of the herbicide atrazine found in the wells of eight Odenton families last year did not come from Fort Meade's sanitary landfill.
The Army tested 27 wells in April that monitor ground water and sampled the soil in 25 spots around the Active Sanitary Land Fill on Fort Meade. The samples detected atrazine, a suspected carcinogen, at less than 3 parts per billion -- a level federal guidelines deem safe for drinking water, said Scott A. Hill, an environmental engineer with the U.S. Army Environmental Center Aberdeen Proving Ground.
Another landfill near the contaminated wells was not sampled for atrazine because the well water does not flow near the dump, known as the Clean Fill Dump, Army officials said.
The Active Sanitary Landfill, which opened in 1958, sits on 130 acres west of Odenton. The Clean Fill Dump, which operated from 1972 to 1985, is west of Woodwardville. The landfills were suspected sources of the herbicide because a 1992 Army report identified them as potential sources of pollution.
The Army will continue its $417,000 study next month and install test wells off base near the contaminated area, said Mr. Hill. A final report will be issued in September.
Meanwhile, the Maryland Department of the Environment is doing its own investigation. This week the state agency sent a letter to AMTRAK, asking to take water samples near tracks that go through Odenton, said Quentin Banks, spokesman for the state agency.
Atrazine has several agricultural uses and is used to control weeds near roads and railroad tracks. The affected area near Odenton has farms, highways and railroads.
Last fall, tests determined that wells at eight homes along Old Waugh Chapel Road had been tainted with atrazine. The level reached or exceeded federal limits at five homes. One home had as much as 8 parts per billion. Three others showed lower levels of contamination.
For several months, Fort Meade and the state Department of the Environment supplied bottled water to residents whose wells have been contaminated.
Anne Arundel County has since brought public water to the families at no charge. The county waived the $4,650 installation fee for each family and paid the plumbing costs.
Ciba-Geigy Corp., the nation's largest maker of atrazine, did not assume liability but reimbursed the county $3,000 for each home whose well was found to have an atrazine level above federal guidelines, said Lisa Ritter, a county spokeswoman.